Mike:
Since it appears to have the long-base rear sight and a "bead" front sight, your carbine is a Canadian cadet carbine, rather than a cavalry carbine.
When Canada finally started phasing out Snider-Enfields as its primary-issue military longarms in 1898, they were so obsolete that no market could be found for them. A decision was made to start issuing the stored cavalry carbines to Cadet Corps, it being a convenient size for boys to handle. However, as Canada only had a few thousand cavalry carbines, the supply of operational ones was soon exhausted, and it was then decided to begin cutting down 3-band rifles to the same general configuration for Cadet issue. They retained the rifle-pattern rear sight, the rod channel in the forestock was plugged with a wooden dowel contoured to the newly-formed forestock nose, and a simple bead was installed for a front sight. (In fact, although still fully functional, these carbines were intended primarily for drilling, not shooting; rather, each Corps was issued with one or more Magazine Lee-Enfield rifles for musketry training. Apparently the bead was placed out front mainly to assist in training boys how to line up a foresight in the rear sight notch because using it as a sight for actual shooting places the point of impact several feet above the point of aim.
From ""The Military Arms of Canada", a comparison of a cavalry carbine and cadet carbine:

Cadet carbines are a unique part of Canadian military history .... they are relatively common in this country, and unfortunately command significantly lower prices than cavalry carbines.
Cavalry carbines had a number of distinctive features: screw heads protruding from the forestock below the rear sight on which a leather sight cover was affixed - as seen above, the rear sight itself was a short-base carbine sight, the front sight was a rounded blade-type , and there was a butt-trap with hinged cover in the buttplate to hold a two-piece clearing rod .....



